Hi all,

I was solving this problem — https://community.topcoder.com/stat?c=problem_statement&pm=14357

I have reduced it to counting number of non-intersecting pair of polygons, but how do I do this? I have looked at other competitor's codes, and they involve fixing two points and counting clockwise and counterclockwise rotations with a third point, but I don't understand how and why this is used. Would appreciate any explanations!

Thanks